I. Technical Field
The present invention relates to an aircraft assembly, such as a main wing and a fuselage of an aircraft, having a lightning protection structure.
II. Description of the Related Art
Accordingly, when using a composite material in a skin, it is required to consider the properties of lightning protection when making a structure, especially a structure that prevents lightning from passing through the fasteners.
As such lightning protection structures, for example, the disclosures of U.S. Pat. No. 4,630,168, specification, and U.S. Pat. No. 5,845,872, specification, have been proposed.
The structure disclosed in U.S. Pat. No. 4,630,168, specification, has an insulating cap attached to an outside end of the head of a fastener, and there have been many proposals for preventing the passage of lightning with such modifications to the structure of a fastener.
In the structure disclosed in U.S. Pat. No. 5,845,872, specification, a metal strap (conductive layer) is attached around a fastener and an insulation layer is provided above the head of the fastener, thereby dispersing the lightening current due to a lightning strike over the skin surface.